I know there are more dedicated websites for this question, but there are a lot of smart folks here. I have the '96 Dodge with the 6BT. I found this fall that when I blocked off part of the radiator, the truck ran warmer and my MPG jumped. My guess is around 2 MPG (I haven't checked it real close yet).

Here's my question - The stock thermostat is 180*F. Cummins never made a hotter thermostat that I could find. From other forums, there is a thermostat for a gas engine that is 195*F that fits. Some of the WVO folks seem to be using these. What are the risks of going to this hotter temperature on this engine? I don't pull much and if I do it isn't very heavy.

Please post if you have any knowledge or experience....not looking for opinions.

Oh, and I should mention the newer 6.7L engines do have a 190*F option.

Are you sure that it dont have a 195 stat? The one for the gasser is a big block dodge but it wont have the correct bypass restriction

I read to drill 2 holes in the one for the big block dodge for this. That was my understanding.

BTW - There's also a 200*F thermostat for the 6.7s

Looks like the newer 6.7 engines starting in 2010 call for the 200*F thermostat. http://www.genosgarage.com/Cooling-System/products/219/ I have read some of the 2nd generation 24v folks on another forum trying the 200*F thermostat's in their truck with a slight gain in fuel mileage.

Remember that with an INTERCOOLED turbo diesel, you are introducing cooled intake air into the engine at all times-that's why a winter front on the grill is used in winter. Not sure the thermostat will make a big difference unless you are towing or hauling heavy loads-a lot of people just put something between the intercooler & radiator with a fan clutch sized hole in the middle to restrict airflow.